Reward and punishment motivate human performance. For example, during unintentional (non-explicit) serial reaction time task (SRTT) learning, punishment boosts early sequence-learning. However, their effect on intentional learning is unknown. We addressed this question in two experiments using the SRTT augmented with control, reward, or punishment feedback. Participants responded to a stimulus in one of four locations; in a block of trials the stimulus followed a fixed- or random-sequence. The difference in RT in sequence and random blocks indexed sequence-knowledge. Trial-by-trial feedback was given based on the participant’s performance. In the first experiment (unintentional learning), 36 participants were equally divided in the three feedback groups; these participants were told not to explicitly learn the sequence. In the second experiment (intentional learning), 36 participants were divided into the three feedback groups and told to explicitly learn the sequence. In both experiments, immediately after training, participants were tested for sequence-knowledge and for awareness. We found that intentionality affected the influence of punishment on sequence-learning. With unintentional learning, punishment boosted early sequence-knowledge, but, with intentional learning, punishment had no effect. Reward did not impact sequence-learning in either experiment and all groups showed equal sequence-knowledge. Finally, intentional learners showed more sequence-awareness than unintentional learners but feedback did not modulate awareness. Together, these results show that intentionality modulates the impact of feedback on early sequence learning: punishment aids unintentional, but not intentional, learning. While the cause remains unclear, this study suggests that feedback’s utility depends on the learner’s goal.